Concrete is a composite material generally defined as a mixture of two components, aggregates and paste. The paste, which typically includes cement, commonly Portland cement, and water, binds the aggregates (sand and gravel or crushed stone) into a rocklike mass as the paste hardens. The paste hardens because of the chemical hydration reaction between the cement and water.
Concrete surfaces have traditionally been polished using a series of finer and finer abrasives to produce a shiny, hard, durable surface. These abrasives may be attached to a machine to move them across the surface. These machines are by nature heavy and normally have a fairly rigid deck which is difficult or at least cumbersome to maneuver.
The majority of concrete slabs are not flat. As machines with fixed abrasives move across the surface, the larger sized grit abrasives extend further down into the undulations on the surface and leave scratches in the low spots. These low spots are very difficult to remove since the abrasive on the next grit of diamond tools only extends outward about half as far as the previous diamond. It therefore cannot reach the low spot created by the abrasive. This issue can often result in exposing the aggregate, because as each diamond is used, it is necessary to drive it down against the surface to try to remove the scratches left from the previous tool. As stock is removed, it requires working either in dust if cutting dry or through a slurry if cutting wet. It is difficult to see what is being accomplished under either condition. If the concrete is hard and the tool being worked with is too hard to fret, then the diamonds will glaze and not remove the previous scratch. If a dry resin bonded diamonds are used, then the scratches fill with resin which comes out later. The end product of dry polished floors is a high gloss with little to no clarity in the floor.
It should be readily apparent from the above that the problems with the grinding and polishing processes are many and varied. Accordingly, there is a continuing need to improve upon existing concrete cutting and polishing systems and methods.